f = File.new("D:\\ez.json")
# f.read
puts f.gets
puts f.gets
# 移动到开头
f.rewind
puts f.readlines
f.rewind
f.each {|line| puts "Next line: #{line}"}

count = 0
total_ages = File.readlines("D:\\ez.json").inject(0) do |total,line|
	count += 1
	age = line.size
	puts age
	total + age
end
puts count

